A type of metallic material exists in one of three possible states: a liquefied state, a solidified state and a slurry state. Generally, the type of metallic material is a metallic alloy that contains two or more metallic elements and/or non-metallic elements that are fused together and/or dissolved into each other. Examples of this type of metallic material are magnesium, aluminum, and zinc, and any combination thereof, or equivalent thereof. The metallic alloy in the slurry state will henceforth be referred to as metallic alloy slurry (MAS). Sometimes, the MAS is called a “thixotropic metallic material”, and the molding machine that processes the MAS is called a “thixo-molding” machine.
U.S. Pat. No. 6,357,511 (Assignee: Husky Injection Molding Systems Ltd.; issued Mar. 19, 2002) discloses a metal alloy injection molding machine (e.g. for magnesium alloy) that has an injection nozzle including a spigot portion whose outer periphery is fitted in channel surface to form seal between surface and periphery of spigot. The '511 teaches abutting a nozzle 11 directly against a feed body 13″.
Published patent application WO 2004/078383 A1 (Assignee: Husky Injection Molding Systems Ltd.) discloses a feed body configured for use in a thixo-molding machine. The '383 teaches abutting a nozzle 50 or a nozzle extension 48 directly against a feed body 52.
U.S. Pat. No. 6,095,789 (Assignee: Polyshot Corporation) discloses a hot sprue bushing for transporting plasticized material from an injection nozzle to a mold cavity comprises an electric heater wrapped around a stem of the bushing. The '789 teaches abutting a nozzle 14 directly against a feed body 24a. 
U.S. Pat. No. 5,213,824 (Assignee: Polyshot Corporation) discloses an adjustable hot sprue bushing for injections molds provided with interchangeable spacing collars. The '824 teaches abutting a nozzle 14 directly against a feed body structure 70.
U.S. Pat. 5,178,886 (Assignee: United Technologies Corporation; issued Jan. 12, 1993) discloses a easily removable injection mold port that includes inwardly widening passage with at least one longitudinal groove to assist removal of hardened plastic by rotating port. The '886 teaches abutting a nozzle 10 directly against a feed body structure 13.
It appears that prior art structures and arrangements pertaining to known feed bodies used in molding machines have persisted for a least 10 years (from Jan. 12, 1993 over to Mar. 19, 2002 as indicated in the prior art identified above) and yet there are ongoing problems with these feed bodies. These feed bodies appear to be prone to rapid onset of stress crack development. It is generally believed that these stress cracks develop as a result of the feed body being exposed to hoop stress due to a high pressure of the MAS, and/or to thermal stress due to a high temperature of the MAS. Disadvantageously, the onset of stress cracks imposes frequent maintenance and/or replacement of the feed body, and/or inadvertent shut down of the thixo-molding machine during production run-time.